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nguyensonckgp
2 năm trước
Kéo một vật năng 100 kg lên cao 25 m bằng Pa lăng gồm 2 rồng rọc động và 2 ròng rọc cố định. Hiệu suất cảu Pa lăng là 80%. Tính a) Công cần thực hiện để nâng vật b) Lực kéo vào đầu dây
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Read the definitions and complete the blanks with given words. goggles court breaststroke stadium volleyball achievement skipping rope boxing tug of war referee No. Definitions Word 1. A sport in which two people fight each ________________ other with their hands, while wearing very large thick gloves 2. A game in which two teams of six ________________ players use their hands to hit a large ball backwards and forwards over a high net while trying not to let the ball touch the ground on their own side 3. A pair of glasses that fit closely to the ________________ face to protect the eyes from wind, dust, water, etc. 4. A thing that somebody has done ________________ successfully, especially using their own effort and skill 5. A style of swimming that you do on ________________ your front, moving your arms and legs away from your body and then back towards it in a circle 6. A place where games such as tennis ________________ are played 7. a type of sport in which two teams ________________ show their strength by pulling against each other at the opposite ends of a rope, and each team tries to pull the other over a line on the ground 8. A piece of rope, usually with a handle ________________ at each end, that you hold, turn over your head and then jump over, for fun or to keep fit 9. A large sports ground surrounded by ________________ rows of seats and usually other buildings 10. A person who is in charge of a sports ________________ game and who makes certain that the rules are followed

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